The problems of lack of efficiency and effectiveness of mobilizing resources lead to unemployment,instability,and underdevelopment of the Nigeria economy.Financial intermediation as a financial system aims at the enha...The problems of lack of efficiency and effectiveness of mobilizing resources lead to unemployment,instability,and underdevelopment of the Nigeria economy.Financial intermediation as a financial system aims at the enhancement of mobilization of funds by pooling individuals savings and increasing the proportion of societal resources devoted to interest—yielding assets and long-term investments,which in turn facilitates economic growth.This study is aimed at accessing the impact of financial intermediation on economic development in Nigeria by using the endogenous components of financial intermediation,such as demand deposits(DD),time/savings deposits(T/Sav),and credits(loans and overdraft),our independent variables as explanatory variables to predict the outcome of our dependent variable output(GDP)secondary data from the CBN(Central Bank of Nigeria)Statistical Bulletin of various issues.The study covers an eight-year period(1995-2014).Parametric statistics in forms of analysis of variance(ANOVA),mean,standard deviation,t-test,co-efficient of correlation,and simple linear regression were used to analyze the data.The findings suggest that though there exists a positive growth relationship between financial intermediation and output in Nigeria,there also exist elements of negative short-run growth relationship,especially for the periods that suffered financial shocks resulting from the global financial crisis and perhaps numerous bank failures.Recommendation states that this finding may serve to buttress existing research outcomes and will be relevant to regulatory authorities in formulating policies that are capable of positively enhancing financial intermediation and output growth in the economy.展开更多
This paper investigates the impacts of financial intermediary （or banking） development on village-level per capita income using a Chinese dataset for selected years between 1993 and 2006. The empirical results from ...This paper investigates the impacts of financial intermediary （or banking） development on village-level per capita income using a Chinese dataset for selected years between 1993 and 2006. The empirical results from a random effect regression model indicate that mean per capita income in rural villages follows an inverted U-shaped path as financial intermediation develops. However, using a pooled quantile regression approach, we find that median per capita income in rural villages follows a positive linear path, rather than an inverted U-shaped path, as financial intermediation develops. The positive linear effect of financial intermediary development is observed at the lower and higher ends of the conditional per capita income distribution. This suggests that development of financial intermediation in China might not have statistically significant differential effects in low-income or high-income rural villages.展开更多
We explore the potential of conducting an experiment in a low Earth orbit spacecraft and using the Earth as a spin and mass source to constrain beyond-the-standard-model(BSM)long-range spin-and velocity-dependent inte...We explore the potential of conducting an experiment in a low Earth orbit spacecraft and using the Earth as a spin and mass source to constrain beyond-the-standard-model(BSM)long-range spin-and velocity-dependent interactions,which are mediated by the exchange of an ultralight(m_(Z')<10^(-10)eV)or massless intermediate vector boson.The high speed of low-Earth-orbit spacecraft can enhance their sensitivity to velocity-dependent interactions.This periodicity enables efficient signal extraction from background noise,thereby improving the accuracy of the experiment.Combining these advantages,we theoretically demonstrate that the novel spacecraft-Earth model can improve the existing bounds on these exotic interactions by up to three orders of magnitude using the China Space Station(CSS)as a representative low-Earthorbit carrier.If successfully implemented,this model may provide an innovative strategy for detecting ultralight dark matter and yield tighter constraints on certain coupling constants of exotic interactions.展开更多
The liquid-only transfer dividing wall column(LDWC)offers a promising path for industrializing dividing wall columns by simplifying vapor split control.However,their energy efficiency is insufficient due to the additi...The liquid-only transfer dividing wall column(LDWC)offers a promising path for industrializing dividing wall columns by simplifying vapor split control.However,their energy efficiency is insufficient due to the addition of heat at the bottom and its removal at the top.Therefore,developing an effective strategy to enhance the energy efficiency of the entire LDWC system is crucial.This work investigates the intensification of LDWC based on the column grand composite curve(CGCC)and thermodynamic analysis,proposing a novel intensification strategy to improve energy efficiency effectively.An optimization model with four blocks is developed to minimize the total annual cost(TAC)of the intensified LDWC.Energy,exergy,economic,and environmental analyses are used to evaluate its performance.Ternary mixtures with different easy separation indexes(ESI)are selected as illustrative examples.For mixtures with ESI≤1,the optimal configuration involves partial feed preheating,compressors and intermediate reboilers on both side sections,along with optimized operating pressure.This setup leads to significant reductions in total energy consumption,TAC,and gas emissions by 43.80%,28.08%,and 42.85%for ESI=1,and by 46.17%,29.06%,and 45.35%for ESI<1,respectively,when compared to conventional distillation sequences(CDS).For mixtures with ESI>1,the best performance is achieved by implementing partial feed preheating and modifications only to the right section.This results in reductions of 21.64%in energy consumption,16.26%in TAC,and 21.51%in gas emissions when compared to CDS.In all cases,the optimal configurations show the lowest lost work and minimum work,indicating an improved thermodynamic performance.展开更多
When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.Howe...When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.However,the key to the efficiency and return on investment of this hybrid energy system lies in the expected lifetime of the SOEC.This study assessed Ni-YSZ|YSZ|GDC|LSC fuel electrode support cells’long-term stability during electrolysis at 650℃with a current density of−0.5Acm^(−2)over 1818 h.The average voltage degradation rate of 2.63%kh^(−1)unfolded in two phases:an initial rapid decay(90 to 1120 h at 3.58%kh^(−1))and a stable decay(1120 to 1818 h at 2.14%kh^(−1)),emphasizing SOECs’probability coupling with nuclear reactors at 650℃.Post-1818-hour electrolysis revealed nickel particle formation associated with Ni(OH)_(x)diffusion and re-deposition,alongside a strontium-containing layer causing interface cracking.Despite minimal strontium segregation in the EDS,XPS data indicated surface segregation of Sr.This study provides crucial insights into prolonged SOEC operation,highlighting both its potential and challenges.展开更多
Ambient-air,moisture-assisted annealing is widely used in fabricating perovskite solar cells(PSCs).However,the inherent sensitivity of perovskite intermediate-phase to moisture—due to fast and spontaneous intermolecu...Ambient-air,moisture-assisted annealing is widely used in fabricating perovskite solar cells(PSCs).However,the inherent sensitivity of perovskite intermediate-phase to moisture—due to fast and spontaneous intermolecular exchange reaction—requires strict control of ambient humidity and immediate thermal annealing treatment,raising manufacturing costs and causing fast nucleation of perovskite films.We report herein a self-buffered molecular migration strategy to slow down the intermolecular exchange reaction by introducing a n-butylammonium bromide shielding layer,which limits moisture diffusion into intermediate-phase film.This further endows the notably wide nucleation time and humidity windows for perovskite crystallization in ambient air.Consequently,the optimized 1.68 e V-bandgap n-i-p structured PSC reaches a record-high reverse-scan(RS)PCE of 22.09%.Furthermore,the versatility and applicability of as-proposed self-buffered molecular migration strategy are certified by employing various shielding materials and 1.53 eV-/1.77 eV-bandgap perovskite materials.The n-i-p structured PSCs based on 1.53 eV-and 1.77 eV-bandgap perovskite films achieve outstanding RS PCEs of 25.23%and 19.09%,respectively,both of which are beyond of the state-of-the-art ambient-air processed PSCs.展开更多
Cation disordering is a common issue in Ni-rich cathodes that significantly degrades cycle life and compromises safety.The cubic rock-salt phase formation and the slow oxidation kinetics of Ni^(2+)during solid-state s...Cation disordering is a common issue in Ni-rich cathodes that significantly degrades cycle life and compromises safety.The cubic rock-salt phase formation and the slow oxidation kinetics of Ni^(2+)during solid-state sintering are widely recognized as the principal causes of these structural defects.To solve this issue,a topotactic soft-chemical precursor engineering strategy is proposed for use in aqueous solution.By utilizing the layered structure of the precursor,this method allows for selective proton extraction and efficient Ni^(2+)oxidation,along with rapid Li+intercalation to form a layered lithiated intermediate.This intermediate crystallizes without further phase transitions during subsequent heat treatment,preventing structural defects caused by complex phase evolution and slow ion diffusion.The resulting cathode exhibits a long-range ordered layered structure and a uniform phase distribution,enabling efficient Li+insertion and extraction.Electrochemical tests reveal a high discharge capacity of 229.6 mAh g^(−1)and an initial coulombic efficiency of 95.77%at 0.1 C,greatly exceeding the performance of a conventionally synthesized cathode(210.3 mAh g^(−1),88.93%).Improved Li^(+)transport kinetics reduces phase-transition hysteresis and alleviates stress concentration,resulting in better cycling stability with a capacity retention of 85.3%after 300 cycles,compared to 61.5%for the conventional sample.This work presents a scalable and effective synthesis route for Ni-rich cathodes with reduced structural disorder and extended lifespan,providing valuable insights into how the regulation of intermediate phases influences electrochemical performance in high-performance Ni-rich cathodes.展开更多
To improve the accuracy of rockburst risk evaluation in mining and tunnelling engineering,the influence of intermediate principal stress σ_(2) deserves further consideration,which has been neglected in general predic...To improve the accuracy of rockburst risk evaluation in mining and tunnelling engineering,the influence of intermediate principal stress σ_(2) deserves further consideration,which has been neglected in general prediction frameworks.This study employs an integrated approach that combines true-triaxial unloading experiments with three-dimensional grain-based discrete element modeling(PFC3D-GBM)to examine the effects of σ_(2) on strain systematically burst and elucidate the underlying mechanisms.Through this dual experimental–numerical methodology,the strainburst characteristics under varying σ_(2) are analyzed in detail regarding mechanical responses,failure evolution and patterns,microscope fracture mechanisms,and energy partitioning.The results indicate that elevated σ_(2) can enhance the bearing capacity of rock,thereby necessitating a higher stress condition required for strainburst.However,it also enlarges the potential strainburst intensity,manifesting as deeper rockburst pits and more violent ejection of rock fragments.An increasing σ_(2) facilitates the microscope transgranular fractures,inhibits intergranular tensile fractures,and raises the kinetic energy conversion ratio slightly.It affects the intensity of strainburst through the following mechanisms,including the increase of energy storage limit,the intensification of Poisson effect for lateral expansion,and the enhancement of the transgranular fracturing mechanism.In practical engineering,the depth and range of support needs to be ensured under high σ_(2) conditions,and it is recommended to use prestressing techniques to control the development of significant slabbing.展开更多
Myelin,made by oligodendrocytes(OLs)in the central nervous system(CNS),is essential for neural transmission.In particular,myelin facilitates communication across the long connections between different brain regions th...Myelin,made by oligodendrocytes(OLs)in the central nervous system(CNS),is essential for neural transmission.In particular,myelin facilitates communication across the long connections between different brain regions that form the white matter.Myelinated segments also provide metabolic intermediates to axons,supporting their demanding energetic needs.Genetic disorders that disrupt myelin formation result in progressive neurologic degeneration.展开更多
Dear Editor,Urea is a vital nitrogen(N)fertilizer in farmland soils and the natural intermediate product of various organonitrogen compounds,such as purines and amino acids(Mobley and Hausinger,1989;Glibert et al.,201...Dear Editor,Urea is a vital nitrogen(N)fertilizer in farmland soils and the natural intermediate product of various organonitrogen compounds,such as purines and amino acids(Mobley and Hausinger,1989;Glibert et al.,2014).Urea in soils is rapidly hydrolyzed to ammonium by urease secreted from ureolytic microorganisms,and then assimilated by plants and microbes or involved in other N cycling pathways,including aerobic and anaerobic ammoxidation(Mobley et al.,1995;Pajares and Bohannan,2016).展开更多
Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we ...Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we found the boosting effects of halogens on organic pollutants formation during thermal processes.In situ electron paramagnetic resonance spectroscopy was used to distinguish the organic free radical intermediates of organic pollutants during thermal processes.The pure chlorine-containing reaction system dominantly induce the formation of highly chlorinated phenoxy radicals,whereas the pure bromine-containing reaction system induce the formation of semiquinone radicals.The results provide clear evidence for the molecular mechanisms by which halogen coexistence boosts pollutants formation.Coexisting halogens made the reactions much more complex.Bromine atom radicals(Br·)can enhance the level of active chlorine atoms radicals(Cl·),then(1)facilitating highly chlorinated organic radicals and toxic pollutants formation,(2)activating polycyclic aromatic hydrocarbons molecules for subsequent ring growth and(3)accelerating oxidation reactions.Combining the identification of organic free radical intermediates and characteristics of products,detailed mechanisms of halogens on the formations of organic pollutants during thermal-related processes were clarified,which can be helpful for their efficient control in the widespread bromines and chlorines co-existence reaction system.展开更多
Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which...Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which are paramount in computational electrocatalysis models.Here,we provide an experimental-computational approach to break down overall adsorption-energy errors into separate gas-phase and adsorbed-phase contributions.The method is evaluated using experimental data and various exchange-correlation functionals and materials for C-and O-containing species.Our main conclusion is that no functional is simultaneously accurate for adsorbates and molecules,as adsorbed-phase errors are visibly different from gas-phase errors.Importantly,total,gas-phase,and adsorbed-phase errors are correlated,revealing intrinsic DFT limitations and enabling the elaboration of swift correction routines.To illustrate the benefits of our approach,we deconvolute and correct all errors in CO_(2)electroreduction to CO and find an agreement with experiments close to chemical accuracy for numerous transition-metal electrodes and all scrutinized functionals.展开更多
The pervasive accumulation of plastic waste exacerbates environmental degradation and undermines resource circularity.Selective thermal catalysis emerges as a transformative pathway for valorizing waste plastics into ...The pervasive accumulation of plastic waste exacerbates environmental degradation and undermines resource circularity.Selective thermal catalysis emerges as a transformative pathway for valorizing waste plastics into value-added chemicals,yet persistent challenges in catalytic activity and product selectivity demand systematic resolution.This review decodes cutting-edge advances in thermal depolymerization by converging two critical dimensions:atomic-scale active site engineering-where rational design of coordination features and interfacial architectures regulates C-C cleavage energetics and intermediate adsorption-and macromolecular-scale manipulation of polymer transient states-leveraging nanoconfinement effects,chain folding dynamics,and thermal fragmentation to accelerate conversion kinetics.We further highlight breakthroughs in operando char-acterization techniques that resolve time-evolving reaction coordinates across catalytic systems.By establishing multiscale structure-activity relationships linking catalyst configurations to polymer dynamics,this analysis derives design paradigms for next-generation upcycling systems.These principles enable economically viable,industrially scalable plastic valorization while charting a strategic trajectory toward carbon-circular economies.展开更多
Liquid core reduction(LCR)technology,originally developed for continuous thin-slab casting,allows space for a submerged entry nozzle in a mold while improving production efficiency.Recent experimental attempts explore...Liquid core reduction(LCR)technology,originally developed for continuous thin-slab casting,allows space for a submerged entry nozzle in a mold while improving production efficiency.Recent experimental attempts explore the implementation of LCR in regular slab casting processes.However,regular slabs(2–3 times thicker than thin slabs)face critical challenges in terms of excessive deformation and stress concentration under external forces,which induce intermediate cracks and thus hinder successful LCR adoption in regular slab production.This study evaluates the feasibility of LCR for producing regular slabs and identifies optimal reduction parameters to prevent crack initiation.A three-dimensional thermal–mechanical coupled model is proposed using the finite element method(FEM),integrated with the equivalent replacement liquid steel(ERLS)method and the normalized Cockcroft–Latham damage model,to achieve quantitative prediction of intermediate crack risk during the LCR process.The ERLS model simulates the extrusion flow and expulsion behavior of the liquid core,and its accuracy is validated against actual production measurements.To identify the critical damage value leading to intermediate crack initiation,this study conducts a consistency analysis between high-temperature tensile tests and FEM-based simulations using damage models.Based on this value,crack prediction is performed for Q355 slabs with cross-sectional dimensions of 170 mm×1450 mm.Using the prediction results,an optimal reduction scheme is determined,wherein the second segment accounts for 50%of the total reduction,the third segment for 32.5%,and the fourth segment for 17.5%,with the theoretical value of maximum reduction being 34 mm.These results provide actionable guidelines for the potential implementation of LCR in regular slab-casting systems.展开更多
Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2]....Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].Toxic intermediates will be produced due to the dysfunction of biochemical pathways.The liver is responsible for many essential metabolic processes,therefore it becomes one of the most severely affected organ by metabolic diseases[3].Early onset of liver disorders in IEMs includes jaundice,hepatomegaly,splenomegaly,ascites,hepatic encephalopathy,and liver failure[4].In infants and young children under 3 years old with acute liver failure(ALF),IEMs account for 18.9%-43%[5].展开更多
Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrat...Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrate that bio-based benzaldehyde,a noteworthy high-value chemical,is able to be directionally prepared from lignocellulosic biomass.This new control-lable transformation was materialized by uniting catalytic-pyrolysis of lignocellulose to toluene intermediate and catalytic oxidation of toluene intermediate to bio-based benzalde-hyde.This work also developed a highly active magnetic catalyst(CoFe_(2)O_(4)@Biochar(HTR)),achieving 77.1%benzaldehyde selectivity and 46.7%benzaldehyde yield using this catalyst.It was found that introducing the biochar carrier into the cobalt iron composite metal oxide cat-alyst enhanced hydroxyl radical formation and bio-based benzaldehyde synthesis.Based on catalyst characterizations and hydroxyl radical analysis,potential reaction mechanism for bio-based benzaldehyde synthesis was proposed.This strategy may provide a beneficial pathway for developing high-value bio-based chemical(benzaldehyde)using renewable lignocellulosic biomass.展开更多
OBJECTIVE:To reveal the antidepressant mechanisms of Jiawei DanZhiXiaoYaoSan(加味丹栀逍遥散,JD)in chronic unpredictable mild stress(CUMS)-induced depression in mice.METHODS:Using the CUMS mouse model of depression,the...OBJECTIVE:To reveal the antidepressant mechanisms of Jiawei DanZhiXiaoYaoSan(加味丹栀逍遥散,JD)in chronic unpredictable mild stress(CUMS)-induced depression in mice.METHODS:Using the CUMS mouse model of depression,the antidepressant effects of JD were assessed using the sucrose preference test(SPT),forced swimming test(FST),and tail suspension test(TST).Tandem mass tag(TMT)-based quantitative proteomic analysis of the brain was performed following JD treatment.Hierarchical clustering,Gene Ontology function annotation,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment,and protein-protein interactions(PPIs)were used to analyze differentially expressed proteins(DEPs),which were further validated using quantitative real-time polymerase chain reaction(qR T-PCR)and Western blotting.RESULTS:Behavioral tests confirmed the antidepressant effects of JD,and bioinformatics analysis revealed 59 DEPs,including 33 up-regulated and 26 down-regulated proteins,between the CUMS and JD-M groups.KEGG and PPI analyses revealed that neurofilament proteins and the Ras signaling pathway may be key targets of JD in the treatment of depression.q RTPCR and Western blotting results demonstrated that CUMS reduced the protein expression of neurofilament light(NEFL)and medium(NEFM)and inhibited the phosphorylation of extracellular regulated kinase 1/2(ERK1/2),whereas JD promoted the phosphorylation of ERK1/2 and up-regulated the protein expression of NEFL and NEFM.CONCLUSIONS:The antidepressant mechanism of JD may be related to the up-regulation of p-ERK1/2 and neurofilament proteins.展开更多
The effects of drawing strain during intermediate annealing on the microstructure and properties of Cu-20 wt%Fe alloy wires while maintaining constant total deformation were investigated.Intermediate annealing effecti...The effects of drawing strain during intermediate annealing on the microstructure and properties of Cu-20 wt%Fe alloy wires while maintaining constant total deformation were investigated.Intermediate annealing effectively removes work hardening in both the Cu matrix and Fe fibers,restoring their plastic deformation capacity and preserving fiber continuity during subsequent redrawing.The process also refines the Fe phase,leading to a more uniform size distribution and straighter,better-aligned Cu/Fe phase interfaces,thereby enhancing the comprehensive properties of the alloy.The magnitude of drawing strain during intermediate annealing plays a critical role in balancing the mechanical strength and electrical conductivity of redrawn wires.A lower initial drawing strain requires greater redrawing strain,leading to excessive hardening of the Fe fibers,which negatively impacts the electrical conductivity and tensile plasticity.Conversely,a higher initial drawing strain can result in insufficient work hardening during the redrawing deformation process,yielding minimal strength improvements.Among the tested alloys,H/3.5 wires show a slight reduction in strength and hardness compared to W and H/4.5 wires but exhibit a significant increase in tensile elongation and electrical conductivity.The tensile strength was 755 MPa,and the electrical conductivity was 47%international-annealed copper standard(IACS).The optimal performance is attributed to the formation of a high-density,ultrafine Fe fiber structure-aligned parallel to the drawing direction,which is achieved through a suitable combination of the drawing process and intermediate annealing.展开更多
Electrocatalytic hydrogen peroxide(H_(2)O_(2))production via the two-electron oxygen reduction reaction(2e−ORR)is promising,but non-metal catalysts with high selectivity are lacking.Herein,a high content of pyrrolic N...Electrocatalytic hydrogen peroxide(H_(2)O_(2))production via the two-electron oxygen reduction reaction(2e−ORR)is promising,but non-metal catalysts with high selectivity are lacking.Herein,a high content of pyrrolic N doped carbon(HPNC)with small mesopores is constructed.Over 80%H_(2)O_(2) selectivity at a wide potential of 0.2–0.6 V is achieved.The finite element simulation reveals that small pore-size mesopores are beneficial to O_(2) adsorption.And in-situ characterization proves that HPNC suppresses the breakage of Osingle bondO bond and enhances the stabilization of *OOH intermediates,thus improving the 2e−ORR performance.This work highlights the combination of non-metal active sites and geometry for 2e−ORR electrocatalysis.展开更多
Fracture(fault)reactivation can lead to dynamic geological hazards including earthquakes,rock collapses,landslides,and rock bursts.True triaxial compression tests were conducted to analyze the fracture reactivation pr...Fracture(fault)reactivation can lead to dynamic geological hazards including earthquakes,rock collapses,landslides,and rock bursts.True triaxial compression tests were conducted to analyze the fracture reactivation process under two different orientations of σ_(2),i.e.σ_(2) parallel to the fracture plane(Scheme 2)and σ_(2) cutting through the fracture plane(Scheme 3),under varying σ_(3) from 10 MPa to 40 MPa.The peak or fracture reactivation strength,deformation,failure mode,and post-peak mechanical behavior of intact(Scheme 1)and pre-fractured(Schemes 2 and 3)specimens were also compared.Results show that for intact specimens,the stress remains nearly constant in the residual sliding stage with no stick-slip,and the newly formed fracture surface only propagates along the σ_(2) direction when σ_(3) ranges from 10 MPa to 30 MPa,while it extends along both σ_(2) and σ_(3) directions when σ_(3) increases to 40 MPa;for the pre-fractured specimens,the fractures are usually reactivated under all the σ_(3) levels in Scheme 2,but fracture reactivation only occurs when σ_(3) is greater than 25 MPa in Scheme 3,below which new faulting traversing the original macro fracture occurs.In all the test schemes,both ε_(2) and ε_(3) experience an accumulative process of elongation,after which an abrupt change occurs at the point of the final failure;the degree of this change is dependent on the orientation of the new faulting or the slip direction of the original fracture,and it is generally more than 10 times larger in the slip direction of the original fracture than in the non-slip direction.Besides,the differential stress(peak stress)required for reactivation and the post-peak stress drop increase with increasing σ_(3).Post-peak stress drop and residual strength in Scheme 3 are generally greater than those in Scheme 2 at the same σ_(3) value.Our study clearly shows that intermediate principal stress orientation not only affects the fracture reactivation strength but also influences the slip deformation and failure modes.These new findings facilitate the mitigation of dynamic geological hazards associated with fracture and fault slip.展开更多
文摘The problems of lack of efficiency and effectiveness of mobilizing resources lead to unemployment,instability,and underdevelopment of the Nigeria economy.Financial intermediation as a financial system aims at the enhancement of mobilization of funds by pooling individuals savings and increasing the proportion of societal resources devoted to interest—yielding assets and long-term investments,which in turn facilitates economic growth.This study is aimed at accessing the impact of financial intermediation on economic development in Nigeria by using the endogenous components of financial intermediation,such as demand deposits(DD),time/savings deposits(T/Sav),and credits(loans and overdraft),our independent variables as explanatory variables to predict the outcome of our dependent variable output(GDP)secondary data from the CBN(Central Bank of Nigeria)Statistical Bulletin of various issues.The study covers an eight-year period(1995-2014).Parametric statistics in forms of analysis of variance(ANOVA),mean,standard deviation,t-test,co-efficient of correlation,and simple linear regression were used to analyze the data.The findings suggest that though there exists a positive growth relationship between financial intermediation and output in Nigeria,there also exist elements of negative short-run growth relationship,especially for the periods that suffered financial shocks resulting from the global financial crisis and perhaps numerous bank failures.Recommendation states that this finding may serve to buttress existing research outcomes and will be relevant to regulatory authorities in formulating policies that are capable of positively enhancing financial intermediation and output growth in the economy.
文摘This paper investigates the impacts of financial intermediary （or banking） development on village-level per capita income using a Chinese dataset for selected years between 1993 and 2006. The empirical results from a random effect regression model indicate that mean per capita income in rural villages follows an inverted U-shaped path as financial intermediation develops. However, using a pooled quantile regression approach, we find that median per capita income in rural villages follows a positive linear path, rather than an inverted U-shaped path, as financial intermediation develops. The positive linear effect of financial intermediary development is observed at the lower and higher ends of the conditional per capita income distribution. This suggests that development of financial intermediation in China might not have statistically significant differential effects in low-income or high-income rural villages.
基金partially supported by the National Key R&D Program of China (Grant No.2023YFA16067003)the National Science Foundation of China (Grant Nos.12435007 and 12522505)。
文摘We explore the potential of conducting an experiment in a low Earth orbit spacecraft and using the Earth as a spin and mass source to constrain beyond-the-standard-model(BSM)long-range spin-and velocity-dependent interactions,which are mediated by the exchange of an ultralight(m_(Z')<10^(-10)eV)or massless intermediate vector boson.The high speed of low-Earth-orbit spacecraft can enhance their sensitivity to velocity-dependent interactions.This periodicity enables efficient signal extraction from background noise,thereby improving the accuracy of the experiment.Combining these advantages,we theoretically demonstrate that the novel spacecraft-Earth model can improve the existing bounds on these exotic interactions by up to three orders of magnitude using the China Space Station(CSS)as a representative low-Earthorbit carrier.If successfully implemented,this model may provide an innovative strategy for detecting ultralight dark matter and yield tighter constraints on certain coupling constants of exotic interactions.
基金support provided by the National Natural Science Foundation of China(U24B6016)the Higher Education Institution Academic Discipline Innovation and Talent Introduction Plan(“111 Plan”)(No.B23025)are gratefully acknowledged.
文摘The liquid-only transfer dividing wall column(LDWC)offers a promising path for industrializing dividing wall columns by simplifying vapor split control.However,their energy efficiency is insufficient due to the addition of heat at the bottom and its removal at the top.Therefore,developing an effective strategy to enhance the energy efficiency of the entire LDWC system is crucial.This work investigates the intensification of LDWC based on the column grand composite curve(CGCC)and thermodynamic analysis,proposing a novel intensification strategy to improve energy efficiency effectively.An optimization model with four blocks is developed to minimize the total annual cost(TAC)of the intensified LDWC.Energy,exergy,economic,and environmental analyses are used to evaluate its performance.Ternary mixtures with different easy separation indexes(ESI)are selected as illustrative examples.For mixtures with ESI≤1,the optimal configuration involves partial feed preheating,compressors and intermediate reboilers on both side sections,along with optimized operating pressure.This setup leads to significant reductions in total energy consumption,TAC,and gas emissions by 43.80%,28.08%,and 42.85%for ESI=1,and by 46.17%,29.06%,and 45.35%for ESI<1,respectively,when compared to conventional distillation sequences(CDS).For mixtures with ESI>1,the best performance is achieved by implementing partial feed preheating and modifications only to the right section.This results in reductions of 21.64%in energy consumption,16.26%in TAC,and 21.51%in gas emissions when compared to CDS.In all cases,the optimal configurations show the lowest lost work and minimum work,indicating an improved thermodynamic performance.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0400000)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2021253)+1 种基金the Major Science and Technology Projects of China National Offshore Oil Corporation Limited during the 14th Five Year Plan(No.KJGG-2022-12-CCUS-030500)the Photon Science Center for Carbon Neutrality of Chinese Academy of Science.
文摘When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.However,the key to the efficiency and return on investment of this hybrid energy system lies in the expected lifetime of the SOEC.This study assessed Ni-YSZ|YSZ|GDC|LSC fuel electrode support cells’long-term stability during electrolysis at 650℃with a current density of−0.5Acm^(−2)over 1818 h.The average voltage degradation rate of 2.63%kh^(−1)unfolded in two phases:an initial rapid decay(90 to 1120 h at 3.58%kh^(−1))and a stable decay(1120 to 1818 h at 2.14%kh^(−1)),emphasizing SOECs’probability coupling with nuclear reactors at 650℃.Post-1818-hour electrolysis revealed nickel particle formation associated with Ni(OH)_(x)diffusion and re-deposition,alongside a strontium-containing layer causing interface cracking.Despite minimal strontium segregation in the EDS,XPS data indicated surface segregation of Sr.This study provides crucial insights into prolonged SOEC operation,highlighting both its potential and challenges.
基金the financial support from the National Key R&D Program of China(2021YFF0500500)the National Natural Science Foundation of China(62474131,62274132,and 62204189)。
文摘Ambient-air,moisture-assisted annealing is widely used in fabricating perovskite solar cells(PSCs).However,the inherent sensitivity of perovskite intermediate-phase to moisture—due to fast and spontaneous intermolecular exchange reaction—requires strict control of ambient humidity and immediate thermal annealing treatment,raising manufacturing costs and causing fast nucleation of perovskite films.We report herein a self-buffered molecular migration strategy to slow down the intermolecular exchange reaction by introducing a n-butylammonium bromide shielding layer,which limits moisture diffusion into intermediate-phase film.This further endows the notably wide nucleation time and humidity windows for perovskite crystallization in ambient air.Consequently,the optimized 1.68 e V-bandgap n-i-p structured PSC reaches a record-high reverse-scan(RS)PCE of 22.09%.Furthermore,the versatility and applicability of as-proposed self-buffered molecular migration strategy are certified by employing various shielding materials and 1.53 eV-/1.77 eV-bandgap perovskite materials.The n-i-p structured PSCs based on 1.53 eV-and 1.77 eV-bandgap perovskite films achieve outstanding RS PCEs of 25.23%and 19.09%,respectively,both of which are beyond of the state-of-the-art ambient-air processed PSCs.
基金the financial support from the Central South University Fundamental Research Funds (Grant No.2025ZZTS0444)the Innovation-Driven Research Program(Grant No. 2023 CXQD053)+3 种基金the National Natural Science Foundation of China (Grant No. 52274310)the financial support (Project No.H202111040350002)the provision of the hydroxide precursors from Ningbo Ronbay New Energy Technology Co.,Ltdsupported in part by the High-Performance Computing Center of Central South University
文摘Cation disordering is a common issue in Ni-rich cathodes that significantly degrades cycle life and compromises safety.The cubic rock-salt phase formation and the slow oxidation kinetics of Ni^(2+)during solid-state sintering are widely recognized as the principal causes of these structural defects.To solve this issue,a topotactic soft-chemical precursor engineering strategy is proposed for use in aqueous solution.By utilizing the layered structure of the precursor,this method allows for selective proton extraction and efficient Ni^(2+)oxidation,along with rapid Li+intercalation to form a layered lithiated intermediate.This intermediate crystallizes without further phase transitions during subsequent heat treatment,preventing structural defects caused by complex phase evolution and slow ion diffusion.The resulting cathode exhibits a long-range ordered layered structure and a uniform phase distribution,enabling efficient Li+insertion and extraction.Electrochemical tests reveal a high discharge capacity of 229.6 mAh g^(−1)and an initial coulombic efficiency of 95.77%at 0.1 C,greatly exceeding the performance of a conventionally synthesized cathode(210.3 mAh g^(−1),88.93%).Improved Li^(+)transport kinetics reduces phase-transition hysteresis and alleviates stress concentration,resulting in better cycling stability with a capacity retention of 85.3%after 300 cycles,compared to 61.5%for the conventional sample.This work presents a scalable and effective synthesis route for Ni-rich cathodes with reduced structural disorder and extended lifespan,providing valuable insights into how the regulation of intermediate phases influences electrochemical performance in high-performance Ni-rich cathodes.
基金supported by the National Natural Science Foundation of China(No.42507210)the Fundamental Research Funds for the Central Universities(No.2025XJSB01)+1 种基金the State Key Laboratory for Tunnel Engineering(No.SKLTEK202421)the Foundation of Key Laboratory of Deep Coal Resource Mining(China University of Mining and Technology),Ministry of Education(No.KLDCRMMOE24KF11).
文摘To improve the accuracy of rockburst risk evaluation in mining and tunnelling engineering,the influence of intermediate principal stress σ_(2) deserves further consideration,which has been neglected in general prediction frameworks.This study employs an integrated approach that combines true-triaxial unloading experiments with three-dimensional grain-based discrete element modeling(PFC3D-GBM)to examine the effects of σ_(2) on strain systematically burst and elucidate the underlying mechanisms.Through this dual experimental–numerical methodology,the strainburst characteristics under varying σ_(2) are analyzed in detail regarding mechanical responses,failure evolution and patterns,microscope fracture mechanisms,and energy partitioning.The results indicate that elevated σ_(2) can enhance the bearing capacity of rock,thereby necessitating a higher stress condition required for strainburst.However,it also enlarges the potential strainburst intensity,manifesting as deeper rockburst pits and more violent ejection of rock fragments.An increasing σ_(2) facilitates the microscope transgranular fractures,inhibits intergranular tensile fractures,and raises the kinetic energy conversion ratio slightly.It affects the intensity of strainburst through the following mechanisms,including the increase of energy storage limit,the intensification of Poisson effect for lateral expansion,and the enhancement of the transgranular fracturing mechanism.In practical engineering,the depth and range of support needs to be ensured under high σ_(2) conditions,and it is recommended to use prestressing techniques to control the development of significant slabbing.
基金support held by JPA,Collaborative Network Award BRAVEinMS,Grant/Award Number:PA-1604-08492(MG)from the Multiple Sclerosis Society of Canada,Grant/Award Number:1038154(to TEK).
文摘Myelin,made by oligodendrocytes(OLs)in the central nervous system(CNS),is essential for neural transmission.In particular,myelin facilitates communication across the long connections between different brain regions that form the white matter.Myelinated segments also provide metabolic intermediates to axons,supporting their demanding energetic needs.Genetic disorders that disrupt myelin formation result in progressive neurologic degeneration.
基金supported by the Funds for International Cooperation and Exchange of the National Natural Science Foundation of China(No.42020104003)。
文摘Dear Editor,Urea is a vital nitrogen(N)fertilizer in farmland soils and the natural intermediate product of various organonitrogen compounds,such as purines and amino acids(Mobley and Hausinger,1989;Glibert et al.,2014).Urea in soils is rapidly hydrolyzed to ammonium by urease secreted from ureolytic microorganisms,and then assimilated by plants and microbes or involved in other N cycling pathways,including aerobic and anaerobic ammoxidation(Mobley et al.,1995;Pajares and Bohannan,2016).
基金supported by the National Key Research and Development Program of China(No.2023YFC3707004)the National Natural Science Foundation of China(Nos.22376204,22076201 and 92143201)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Nos.XDB0750400,XDB0750100 and XDB0750000)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(No.2019 QZKK0605).
文摘Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we found the boosting effects of halogens on organic pollutants formation during thermal processes.In situ electron paramagnetic resonance spectroscopy was used to distinguish the organic free radical intermediates of organic pollutants during thermal processes.The pure chlorine-containing reaction system dominantly induce the formation of highly chlorinated phenoxy radicals,whereas the pure bromine-containing reaction system induce the formation of semiquinone radicals.The results provide clear evidence for the molecular mechanisms by which halogen coexistence boosts pollutants formation.Coexisting halogens made the reactions much more complex.Bromine atom radicals(Br·)can enhance the level of active chlorine atoms radicals(Cl·),then(1)facilitating highly chlorinated organic radicals and toxic pollutants formation,(2)activating polycyclic aromatic hydrocarbons molecules for subsequent ring growth and(3)accelerating oxidation reactions.Combining the identification of organic free radical intermediates and characteristics of products,detailed mechanisms of halogens on the formations of organic pollutants during thermal-related processes were clarified,which can be helpful for their efficient control in the widespread bromines and chlorines co-existence reaction system.
基金financial support from MICIU/AEI/10.13039/501100011033by the European Union,and grant MOE-T2EP10222-0007 from the Ministry of Education,Singapore。
文摘Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which are paramount in computational electrocatalysis models.Here,we provide an experimental-computational approach to break down overall adsorption-energy errors into separate gas-phase and adsorbed-phase contributions.The method is evaluated using experimental data and various exchange-correlation functionals and materials for C-and O-containing species.Our main conclusion is that no functional is simultaneously accurate for adsorbates and molecules,as adsorbed-phase errors are visibly different from gas-phase errors.Importantly,total,gas-phase,and adsorbed-phase errors are correlated,revealing intrinsic DFT limitations and enabling the elaboration of swift correction routines.To illustrate the benefits of our approach,we deconvolute and correct all errors in CO_(2)electroreduction to CO and find an agreement with experiments close to chemical accuracy for numerous transition-metal electrodes and all scrutinized functionals.
基金supported by the Key Technologies Research and Development Program(2024YFC2909605)Black Soil Project of Shenyang Science and Technology Program(24-216-2-07)Fundamental Research Funds for the Central Universities(NO.N25BSS006).
文摘The pervasive accumulation of plastic waste exacerbates environmental degradation and undermines resource circularity.Selective thermal catalysis emerges as a transformative pathway for valorizing waste plastics into value-added chemicals,yet persistent challenges in catalytic activity and product selectivity demand systematic resolution.This review decodes cutting-edge advances in thermal depolymerization by converging two critical dimensions:atomic-scale active site engineering-where rational design of coordination features and interfacial architectures regulates C-C cleavage energetics and intermediate adsorption-and macromolecular-scale manipulation of polymer transient states-leveraging nanoconfinement effects,chain folding dynamics,and thermal fragmentation to accelerate conversion kinetics.We further highlight breakthroughs in operando char-acterization techniques that resolve time-evolving reaction coordinates across catalytic systems.By establishing multiscale structure-activity relationships linking catalyst configurations to polymer dynamics,this analysis derives design paradigms for next-generation upcycling systems.These principles enable economically viable,industrially scalable plastic valorization while charting a strategic trajectory toward carbon-circular economies.
基金financially supported by the Na-tional Natural Science Foundation of China (No.52474355)the Fundamental Research Funds for the Central Uni-versities,China (No.N25DCG006).
文摘Liquid core reduction(LCR)technology,originally developed for continuous thin-slab casting,allows space for a submerged entry nozzle in a mold while improving production efficiency.Recent experimental attempts explore the implementation of LCR in regular slab casting processes.However,regular slabs(2–3 times thicker than thin slabs)face critical challenges in terms of excessive deformation and stress concentration under external forces,which induce intermediate cracks and thus hinder successful LCR adoption in regular slab production.This study evaluates the feasibility of LCR for producing regular slabs and identifies optimal reduction parameters to prevent crack initiation.A three-dimensional thermal–mechanical coupled model is proposed using the finite element method(FEM),integrated with the equivalent replacement liquid steel(ERLS)method and the normalized Cockcroft–Latham damage model,to achieve quantitative prediction of intermediate crack risk during the LCR process.The ERLS model simulates the extrusion flow and expulsion behavior of the liquid core,and its accuracy is validated against actual production measurements.To identify the critical damage value leading to intermediate crack initiation,this study conducts a consistency analysis between high-temperature tensile tests and FEM-based simulations using damage models.Based on this value,crack prediction is performed for Q355 slabs with cross-sectional dimensions of 170 mm×1450 mm.Using the prediction results,an optimal reduction scheme is determined,wherein the second segment accounts for 50%of the total reduction,the third segment for 32.5%,and the fourth segment for 17.5%,with the theoretical value of maximum reduction being 34 mm.These results provide actionable guidelines for the potential implementation of LCR in regular slab-casting systems.
文摘Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].Toxic intermediates will be produced due to the dysfunction of biochemical pathways.The liver is responsible for many essential metabolic processes,therefore it becomes one of the most severely affected organ by metabolic diseases[3].Early onset of liver disorders in IEMs includes jaundice,hepatomegaly,splenomegaly,ascites,hepatic encephalopathy,and liver failure[4].In infants and young children under 3 years old with acute liver failure(ALF),IEMs account for 18.9%-43%[5].
基金supported by the National Natural Sci-ence Foundation of China(Nos.U21A20288 and 21978280).
文摘Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrate that bio-based benzaldehyde,a noteworthy high-value chemical,is able to be directionally prepared from lignocellulosic biomass.This new control-lable transformation was materialized by uniting catalytic-pyrolysis of lignocellulose to toluene intermediate and catalytic oxidation of toluene intermediate to bio-based benzalde-hyde.This work also developed a highly active magnetic catalyst(CoFe_(2)O_(4)@Biochar(HTR)),achieving 77.1%benzaldehyde selectivity and 46.7%benzaldehyde yield using this catalyst.It was found that introducing the biochar carrier into the cobalt iron composite metal oxide cat-alyst enhanced hydroxyl radical formation and bio-based benzaldehyde synthesis.Based on catalyst characterizations and hydroxyl radical analysis,potential reaction mechanism for bio-based benzaldehyde synthesis was proposed.This strategy may provide a beneficial pathway for developing high-value bio-based chemical(benzaldehyde)using renewable lignocellulosic biomass.
基金the National Natural Science Foundation of China:Study on the Biological Basis of Jiawei Danzhi Xiaoyaosan in Treatment of Depression based on Network Pharmacology and Proteomics(No.81973739)Natural Science Excellent Youth Fund of Henan Province:the Mechanism of Baicalin Regulates the GSK3B-Mediated Axoplasmic Transport in the Treatment of Depression(No.202300410249)+1 种基金Science and Technology Research Project of Henan Province:Study on the Antidepressant Mechanism of Jiawei Danzhi Xiaoyaosan based on the NOD-like Receptor Thermal Protein Domainassociated Protein and Tripartite Motif-containing Protein 31 Ubiquitination Pathway(No.222102310233)Study on the Mechanism of Jiawei Danzhi Xiaoyaosan in the Treatment of Depression by Regulating M1/M2 Polarization and Microglia Autophagy(No.232102310419)。
文摘OBJECTIVE:To reveal the antidepressant mechanisms of Jiawei DanZhiXiaoYaoSan(加味丹栀逍遥散,JD)in chronic unpredictable mild stress(CUMS)-induced depression in mice.METHODS:Using the CUMS mouse model of depression,the antidepressant effects of JD were assessed using the sucrose preference test(SPT),forced swimming test(FST),and tail suspension test(TST).Tandem mass tag(TMT)-based quantitative proteomic analysis of the brain was performed following JD treatment.Hierarchical clustering,Gene Ontology function annotation,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment,and protein-protein interactions(PPIs)were used to analyze differentially expressed proteins(DEPs),which were further validated using quantitative real-time polymerase chain reaction(qR T-PCR)and Western blotting.RESULTS:Behavioral tests confirmed the antidepressant effects of JD,and bioinformatics analysis revealed 59 DEPs,including 33 up-regulated and 26 down-regulated proteins,between the CUMS and JD-M groups.KEGG and PPI analyses revealed that neurofilament proteins and the Ras signaling pathway may be key targets of JD in the treatment of depression.q RTPCR and Western blotting results demonstrated that CUMS reduced the protein expression of neurofilament light(NEFL)and medium(NEFM)and inhibited the phosphorylation of extracellular regulated kinase 1/2(ERK1/2),whereas JD promoted the phosphorylation of ERK1/2 and up-regulated the protein expression of NEFL and NEFM.CONCLUSIONS:The antidepressant mechanism of JD may be related to the up-regulation of p-ERK1/2 and neurofilament proteins.
基金support provided by the National Natural Science Foundation of China(Nos.52405364,and 52171110)the Jiangsu Funding Program for Excellent Postdoctoral Talent.W.Huo acknowledges the support from the European Union Horizon 2020 Research and Innovation Program(No.857470)+1 种基金from the European Regional Development Fund via the Foundation for Polish Science International Research Agenda PLUS Program(No.MAB PLUS/2018/8)The publication was partly created within the framework of the project of the Minister of Science and Higher Education"Support for the activities of Centers of Excellence established in Poland under Horizon 2020"(No.MEiN/2023/DIR/3795).
文摘The effects of drawing strain during intermediate annealing on the microstructure and properties of Cu-20 wt%Fe alloy wires while maintaining constant total deformation were investigated.Intermediate annealing effectively removes work hardening in both the Cu matrix and Fe fibers,restoring their plastic deformation capacity and preserving fiber continuity during subsequent redrawing.The process also refines the Fe phase,leading to a more uniform size distribution and straighter,better-aligned Cu/Fe phase interfaces,thereby enhancing the comprehensive properties of the alloy.The magnitude of drawing strain during intermediate annealing plays a critical role in balancing the mechanical strength and electrical conductivity of redrawn wires.A lower initial drawing strain requires greater redrawing strain,leading to excessive hardening of the Fe fibers,which negatively impacts the electrical conductivity and tensile plasticity.Conversely,a higher initial drawing strain can result in insufficient work hardening during the redrawing deformation process,yielding minimal strength improvements.Among the tested alloys,H/3.5 wires show a slight reduction in strength and hardness compared to W and H/4.5 wires but exhibit a significant increase in tensile elongation and electrical conductivity.The tensile strength was 755 MPa,and the electrical conductivity was 47%international-annealed copper standard(IACS).The optimal performance is attributed to the formation of a high-density,ultrafine Fe fiber structure-aligned parallel to the drawing direction,which is achieved through a suitable combination of the drawing process and intermediate annealing.
文摘Electrocatalytic hydrogen peroxide(H_(2)O_(2))production via the two-electron oxygen reduction reaction(2e−ORR)is promising,but non-metal catalysts with high selectivity are lacking.Herein,a high content of pyrrolic N doped carbon(HPNC)with small mesopores is constructed.Over 80%H_(2)O_(2) selectivity at a wide potential of 0.2–0.6 V is achieved.The finite element simulation reveals that small pore-size mesopores are beneficial to O_(2) adsorption.And in-situ characterization proves that HPNC suppresses the breakage of Osingle bondO bond and enhances the stabilization of *OOH intermediates,thus improving the 2e−ORR performance.This work highlights the combination of non-metal active sites and geometry for 2e−ORR electrocatalysis.
基金funding support from the National Nature Science Foundation of China(Grant No.42272334)the National Key Research and Development Program of China(Grant No.2022YFE0137200)the Taishan Scholars Program(Grant No.2019RKB01083).
文摘Fracture(fault)reactivation can lead to dynamic geological hazards including earthquakes,rock collapses,landslides,and rock bursts.True triaxial compression tests were conducted to analyze the fracture reactivation process under two different orientations of σ_(2),i.e.σ_(2) parallel to the fracture plane(Scheme 2)and σ_(2) cutting through the fracture plane(Scheme 3),under varying σ_(3) from 10 MPa to 40 MPa.The peak or fracture reactivation strength,deformation,failure mode,and post-peak mechanical behavior of intact(Scheme 1)and pre-fractured(Schemes 2 and 3)specimens were also compared.Results show that for intact specimens,the stress remains nearly constant in the residual sliding stage with no stick-slip,and the newly formed fracture surface only propagates along the σ_(2) direction when σ_(3) ranges from 10 MPa to 30 MPa,while it extends along both σ_(2) and σ_(3) directions when σ_(3) increases to 40 MPa;for the pre-fractured specimens,the fractures are usually reactivated under all the σ_(3) levels in Scheme 2,but fracture reactivation only occurs when σ_(3) is greater than 25 MPa in Scheme 3,below which new faulting traversing the original macro fracture occurs.In all the test schemes,both ε_(2) and ε_(3) experience an accumulative process of elongation,after which an abrupt change occurs at the point of the final failure;the degree of this change is dependent on the orientation of the new faulting or the slip direction of the original fracture,and it is generally more than 10 times larger in the slip direction of the original fracture than in the non-slip direction.Besides,the differential stress(peak stress)required for reactivation and the post-peak stress drop increase with increasing σ_(3).Post-peak stress drop and residual strength in Scheme 3 are generally greater than those in Scheme 2 at the same σ_(3) value.Our study clearly shows that intermediate principal stress orientation not only affects the fracture reactivation strength but also influences the slip deformation and failure modes.These new findings facilitate the mitigation of dynamic geological hazards associated with fracture and fault slip.
